Mexico needs water. And he’s already looking for a way to get it. Its capital is suffering from a drought problem that at the beginning of this week kept the three dams of the Cutzamala System —the one that supplies the population and industry of CDMX and the central-south region— with a deficit of 23.1% in their levels of storage. To alleviate the situation, the authorities have chosen to explore options. Some orthodox, such as looking for saving strategies or rehabilitating wells. And others that are somewhat less so, such as “bombing” clouds to encourage rain.
What does it consist of exactly? And above all… Does it work?
Objective: combat drought. That is the great challenge. Data published Tuesday by El Financiero show that the El Bosque dam was at 50.3%, the Vila Victoria dam at 37.6% and the Valle de Bravo dam at 51.5%. If the Cutzamala System as a whole is analyzed, the commission to supply CDMX and the State of Mexico, the deficit is 23.1%, a percentage that is explained by a record of average rainfall much lower than the average in CDMX and the Basin of the Mexican Valley.
A look at the latest drought map from the National Water Commission (Conagua) and the meteorological service (SMN), published on March 18, helps to understand how the drought affects the nation, especially stubborn in the central region and certain points cataloged with the label of “extreme drought”. According to Conagua calculations, more than 80% of the country suffers from a lack of rain. The worst unemployed: the states of Nuevo León, Tamaulipas and Michoacán.
On the hunt for solutions. Faced with this scenario, the authorities have chosen to make a move and seek solutions. Water saving strategies have been put on the table, plans for a better use of resources, negotiations with companies so that they give up part of the supply to which they are entitled… And, that is, the “cloud bombardment”, as The Ministry of Defense (Sedena) will apply. The solution may be striking, but it is not entirely new: in 2022 the Government of Nuevo León announced it precisely to deal with the famine.
The objective is relatively simple, at least on paper: launch chemical agents with the help of an airplane so that they favor the rains. As detailed by the Secretary of National Defense, Luis Cresencio Sandoval, they want to take advantage of the “very good conditions” of humidity and cloudiness registered in the Cutzamala area. “It will generate that the dams of all that part can be loaded with enough water,” he claims. The objective of the authorities is that the “cloud bombardments” start this month and continue throughout April and May.
What is the “bombardment”? “Bombardment” or “sowing”, another of the expressions that is also frequently used to describe a method that actually dates back to the 1940s. Its mechanics is quite simple: particles of silver iodide or other aerosols are released in clouds with certain conditions to encourage rain or snowfall. When applying the system, airplanes, rockets can be used or work from the ground and operate with different types of clouds.
Over the decades, the system has been used to deal with droughts and low water levels such as those that Mexico now faces, but also for other purposes, to which Spain is no stranger. In Madrid or Aragon they have used it to protect crops from hailstorms and there are places where it has been tested to produce snow.
Is Mexico the first to use it? No, of course not. In the United Arab Emirates (UAE) they have used fleets of drones to seed clouds and generate artificial rain, in China an ambitious plan was launched last year to cover an area of 6,000 square kilometers and on the other side of the Atlantic, in the US, states such as Idaho, Utah, Colorado or California have also tested the possibilities of the strategy. The method has also been explored in Spain.
But it works? Here’s the million dollar question. And as often happens, the answer is not simple. “Experiments that produce snow or rain require the right type of clouds, with sufficient moisture, and suitable temperature and wind conditions. The percentage increases are small, and it is difficult to know when the snow or rain fell naturally and when it was triggered. by planting,” explains William R. Cotton of Colorado State University.
“Most of the studies aimed at evaluating the effects of seeding cumulus clouds have shown little or no effect,” the expert adds, and clarifies: “Despite the results of seeding winter orographic clouds, those that form when the air towers over a mountain, have shown increases in precipitation. By way of data for reflection, Cotton recalls the wide disparity of figures that studies on the subject have produced.
Does that mean it doesn’t work? The answer is complicated again. In his article, Cotton cites a 2020 study showing snowfall was recorded just 20 minutes after planting, and other experts are convinced the method is effective. “It works. We know this from experiments in the laboratory. We have enough evidence that it works in nature. The thing is, we still don’t have a great understanding of the amount of water we can produce,” says Katja Friedrich, a scientist and author of the study. SNOWIE.
The system has also earned the trust of a good handful of countries and organizations, beyond Mexico. The World Meteorological Organization (WMO) estimates that at least in 2017 there were more than fifty nations applying weather modification programs to induce an increase in rain and snow or minimize the effect of hailstorms on agricultural crops.
Images: Jezael Melgoza (Unsplash) and SMN
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Via: Xataka Mexico
